Definition
A course-reversal maneuver flown during a teardrop approach in which the aircraft tracks outbound from a fix on a specified heading, then turns inbound to intercept the final approach course while descending toward the airport or final approach fix.
Plain English
A turn used to reverse direction during a teardrop approach. You fly outbound on one heading, then turn back toward the airport, descending as you go so you arrive at the right altitude on the final approach course.
Context Anchor
Seen in instrument approach training and on approach charts that use a teardrop course reversal.
Derivation
Penetration' comes from the Latin penetrare, meaning to pass into or through. In this procedure, the turn is the point where the aircraft begins penetrating downward through the airspace toward the airport, descending from the initial approach altitude to the final approach altitude.
Why Pilots Care
Correct execution ensures proper course alignment and controlled descent so the aircraft arrives at the final approach fix at the right altitude and heading.
Intuition Check
“Penetration” does not mean pushing through a storm or restricted airspace here. It means using a published turn to enter and line up with the instrument approach path.
Example Sentence 1
After crossing the fix outbound, the pilot began the penetration turn and started the descent toward the final approach altitude.
Example Sentence 2
During the teardrop procedure the penetration turn was completed before reaching the final approach fix.